Spokesman Jim McGrath said Bush likes both a surprise and an adrenaline rush.

"It's vintage George Bush," McGrath said. "It's that passion for life. It's wanting to set a goal, wanting to achieve it. I'm sure part of it is sending a message to others that even in your retirement years you can still find challenges."

The first time Bush jumped from an airplane was when his plane was shot down in World War II over the Pacific. Later, he decided to jump from a plane of his own accord and marked his 75th, 80th and 85th birthdays by skydiving.

He said on his 85th birthday that he'd like to do it again on his 90th.